The var attribute defines a variable named row, which is used to access the current row's data during rendering.

var属性定义一个变量，称为row，可用来在呈现期间访问当前行的数据。

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The SetValueBindingHandler just defines a variable and puts the variable in the Facelets scope so your logic tags can reuse the variable.

SetValueBindingHandler 只定义了一个变量并把变量放置在 Facelets 作用域内，这样您的逻辑标记就可以重用该变量。

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However, SetValueBindingHandler just defines a variable (whatever var is set to; for example, "vb") to the value binding that was passed. Listing 11 shows the code to override the apply method.

但是，SetValueBindingHandler只为所传递的值绑定定义了一个变量(不论var设置为何值；例如，“vb”)。

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